Malaria Flashcards
Most common and most severe type of malaria
Falciparum
Features of severe malaria
schizonts on a blood film
parasitaemia > 2%
hypoglycaemia
acidosis
temperature > 39 °C
severe anaemia
Parasitaemia over what % means severe malaria?
> 2%
Complications of severe malaria
- cerebral malaria: seizures, coma
- renal failure: blackwater fever, (intravascular haemolysis)
- ARDS
- hypoglycaemia
- disseminated intravascular coagulation (DIC)
Treatment of uncomplicated falciparum malaria
artemisinin-based combination therapies (ACTs)
- artemether
+ lumefantrine
+ amodiaquine
+ mefloquine
+ sulfadoxine-pyrimethamine,
- dihydroartemisinin plus piperaquine
Treatment of complicated falciparum malaria
parenteral drugs
consider exchange transfusion if parasitaemia >10%
A parasite count over what percentage should prompt exchange transfusion?
parasite count > 10%
Gold standard diagnostic investigation for malaria?
Blood film
What is the difference between a thick and thin blood film?
thick: more sensitive
thin: determines species
What rapid diagnostic test can be used to look for malaria
detection of plasmodial histidine-rich protein 2
Signs of malaria on FBC
thrombocythaemia
normochromic normocytic anaemia
normal white cell count
reticulocytosis
Causes of non-falciparum malaria
Plasmodium vivax (most common)
Plasmodium ovale
Plasmodium malariae
Where are the non-falciparum malaria species commonly found?
Plasmodium vivax
- Central America and the Indian Subcontinent
Plasmodium ovale - Africa.
Features of non-falciparum malaria
- fever (every 48/72 hrs)
- headache
- splenomegaly
- Plasmodium malariae is associated with nephrotic syndrome.
Why do plasmodium ovale/vivax often relapse after treatment?
they have a hypnozoite stage
**patients should be given primaquine following acute treatment with chloroquine to destroy liver hypnozoites and prevent relapse
Treatment of non-falciparum malaria
- artemisinin-based combination therapy (ACT) or chloroquine (if not resistant)
In what patient group should ACT treatment be avoided?
ACTs should be avoided in pregnant women
When should Atovaquone + proguanil (Malarone) be taken as prophylaxis?
1 - 2 days before travel,
until 7 days after travel
Main side effect of Atovaquone + proguanil (Malarone)
GI upset
For how long should chloroquine be taken as malaria prophylaxis?
1 week before, until
4 weeks after
Taken ONCE WEEKLY
Chloroquine side effects and contraindications
headache
C/I in epilepsy
For how long should doxycycline be taken as prophylaxis?
1-2 days before travel until 4 weeks after
Doxycycline side effects
photosensitivity
oesophagitis
For how long should Mefloquine (Lariam) be taken as malaria prophylaxis?
2-3 weeks prior to travel, until 4 weeeks after
**Taken ONCE WEEKLY
Side effects and contraindications of Mefloquine (Lariam)?
Dizziness
Neuropsychiatric disturbance
C/I in epilepy
For how long should Proguanil (Paludrine) or Proguanil + chloroquinebe taken as malaria prophylaxis?
From 1 week prior to travel, until 4 weeks after
Why may parasites not be detected on blood films in pregnant patients?
Placental sequestration
Malaria prophylaxis in pregnancy
- ideally don’t travel to malaria endemic area
- chloroquine
- Folate supplementation
Malaria prophylaxis in children
- diethyltoluamide (DEET) 20-50% (used children >2 months)
- doxycycline if >12 years
